Body Fat Percentage Explained

Do you know your Body Fat Percentage?

What most people mean when they want to "lose weight" is to lose fat. Losing too much weight can however mean that you lose muscle tissue and other important body elements. You should always keep in mind that a certain amount of body fat is important and even essential for survival.

To better understand body fat percentage we need to break your weight down into:

Lean Body Mass: This is your weight if you have 0% body fat and your weigth only consists of muscle, organs, blood, bones e.t.c (fat excluded).

Total Body Mass: This is your Lean Body Mass PLUS your fat weight.

Lets see what it means with a real example. Suppose you are 180 pounds and have 20% body fat percentage your:

Lean Body Mass is: 180 x 0.8 = 144 pounds

Fat weight = 180 x 0.2 = 36 pounds

Total body weight = 180 pounds

A certain amount of fat is essential for survival and well being.  Fat regulates body temperature, cushions and insulates organs and tissues and is the main form of the body's energy storage.

The following table describes body fat ranges and their associated categories:

Category (Adults only)	Woman	Men
Essential	10-13%	2-5%
Athletes	14-20%	6-13%
Fitness	20-24%	13-17%
Acceptable	24-31%	17-25%
Overweight / Obese	>31%	>25%

Note: This table is only applicable for adults and is from the American Council on Exercise.

Take the Body Fat Calculator test at the top of this page. It will calculate your body fat percentage, body mass index and resting metabolic rate. All of them are good indicators of your body type and health.

Your body fat percentage is helpful to determine realistic weight loss goals but remember that weight loss doesn't always mean fat loss. Losing to much weight usually also means you lose muscle tissue important for your metabolism and strength.

Lets use this as an example:

You're a woman with 20% body fat and your weight is 120 pounds. Your goals is to lose 15 pounds.

Initial body fat: 120 x 0.20% fat = 24 pounds body fat

Lean body mass: 120 total - 24 pound fat = 96 pounds lean body mass

Your goal: 120 - 15 = 105 pounds

Body fat percentage: 105 / 96 = 9.3% body fat

You would in this case only have a 9.3% body fat percentage. This is below the essential body fat percentage for woman according to the table above. It's clearly not healthy and could even be dangerous for you.

Losing this much weight would mean that you also start losing muscle tissue. This is of course not desirable as muscle tissue is metabolically active and calorie burning.

If you instead take another approach and target 20% body fat you will get a much more realistic and healthy goal.

You would in this case have:

Lean body mass: 120 total - 24 pound fat = 96 pounds lean body mass

Targeted Body fat weight: 96 pounds x 0.2 = 19.2 pounds

Your targeted total weight: 96 + 19.2 = 115.2 pounds

Total weight loss needed: 120 - 115.2 = 4.8 pounds

To get a lean, healthy body similar to an athlete you would only have to lose 4.8 pounds in contrast to your previous goal of 15 pounds.

The conclusion from this is that you must set your weight loss goals realistic and body fat percentage is a good measure how much weight you can lose while still staying healthy.

**On the right side of the page you can find a link where you can calculate your body fat percentage.